DFJY30 Product Specification

Input Voltage: 3.7V ~ 4.2V
Output Power: 7W ~30 W
Load Capacity: 0.4ohm~2.8ohm(Full Power)
Quiescent Current: <300uA

Low-voltage protection:  Input Voltage is lower than 3.4V protection, no output
High-voltage protection: Input Voltage is higher than 5V protection, no output
Charging function:  With charging function, charging voltage: 4.75V~5.25V
Short circuit protection: Load resistance is lower than 0.2 Ohms protection, no output Open circuit protection: Load resistance is higher than 4 Ohms protection, no output

Reverse  Protection  of  Battery Polarity :
Product with battery polarity reversed cannot work 

Other Features: 
1,  Load resistance between 2.8ohm~4ohm, can output,  output power  can be geten when power is counted with load resistance 2.8ohm.
2,  Power values can be saved, and will not disappear when power down.
3,  Single button control.